Improvement in hot-air engine



No. 91,239. PATENTED JUNE 15, 1869. w. LEBMANN. .HOT AIR ENGINE.

3 SHEETS-SHEET 1.

THE cams mans co FHOTOUTNQ. ws-mmv. a c.

TATENTED JUNE 15, 1869.

Ow no 2 9 W. LEI-IM ANN. HOT AIR ENGINE.

/vM/V////// whassea' adv/1%) 4/MW No. 91,239. PATENTED JUNE 15, 1869.

- W. LEHMANN.

HOT AIR ENGINE.

3 SHEETS-SHEET 3.

77Zmwar 172m? I limited some;

attnt Qtllfliw.

WILHELM LEHMANN, OF NUREMBERG, GERMANY, ASSIGNOR TO HIMSELF AND STEI IN & WULFING, OF NEW YORK Cl'lY.

Let-tors Patent No, 91,239, dated June 15, 1869.

IMPROVEMENT IN HOT-AIR ENGINE.

The Schedule referred to in these Letters Patent and making part of the lame.

To all whom it may concern.-

Figure 1 is a longitudinal section of said caloric-.

engine;

Figure 2 is a plan of the same; and

Figure 3 is a front elevation.

Similar letters denote the same parts.

The object of this invention is to protect the packings and working-parts from injury by the heat, dust, and friction usual in hot-air engines, and that the oil, or lubricating-material, can be used without being charred. I

In consequence of my peculiar construction, high speed and increased power can be obtained in proportion to the size of the engine.

There is no unpleasant smell from the oil. The volume of air employed is confined in the engine, and but little inconvenience is experienced from these engines, even in warm weather.

. Any character of fuel may be employed. There is no danger of explosions, and the engine is simple in its construction, can be attended by an ordinary mechanic, and can be very easily kept in repair.

My invention consists in an air-heating-vessel, or hat, with a closed end, placed in a furnace and connected with the engine-cyliinler, in combination with a main piston and a displacement-cylinder, and a waterjacket surrouinling the main cylinder.

By this construction the air between the displacement-cylinder and piston is forced into the space hetwecn tln. displacement-cylinder and hat. There it heated, and acts to move the displacement-cylinder. Then the further movement of the parts causes the air to pass between the displacement-cylinder and the main cylinder, so that it is cooled and its bulk lessened, allowing of the reverse movement of the engine.

In the drawing- A is the main cylinder, to which is united, by the bolts s,the air-heating vessel D, the end of which is shaped somewhat like a hat, and is to be introduced within any suitable furnace or heatidg-apparatns.

I have shown a furnace, R.

The end-portion of this air-heating vessel D is re movable, so as to be changed in case of being burned out.

Around the cylinder A is a water-jacket, W, with an inlet at F, and an escape-pipe, F.

These are to be connected with a reservoir, and the water should circulate through the jacket sons to be keptcool, and, where the body of water is snflicient to diffuse the caloric, it will not be necessary to replenish the same on account of,bccoming warm.

The cylinders A andD contain the displacing-cylinder G, that is made of sheet-metal, riveted firmly, so as to be air-tight, and within it is a head, g, and, at the end next the piston K, is a head, g.

This cylinder G is fitted to slide freely, in brass or other guides, attached to the inside of the cylinder A, as at 12, there being an air-passage between the cylinders G and A. g

The piston-rod d is connected to the heads g g, and passes through a standing-box in the piston K, and connects, by slings 2 2, with the crank H, on a rock-shaft, 3, an arm, 4, from which connects, by the rod u, with the crank l), on crank M of the shaft 5 of the fly-wheel S.

The piston K is connected, by the links 6, to the crank-arms 7, on the rock-shaft 8, and, from the arm H, a link, a, connects to the crank M.

A valve, V, is provided, that can be operated by the handle q, or by the governor N, to let air into the engine, or allow air to pass out, if necessary.

The governor N is of any usual character, and forms no part/of this invention.

:It will be understood, upon reference to fig. 1, that the fly-wheel S, moving in the direction shown by the arrow, the displacemcut-cylinder G moves toward K, and that the piston K, for a short distance, moves toward g.

The cranks H H are so placed that this movement takes place to expel the air from betwcen'g and K, and-send it into the hat D.

There it is heated, 'and acts, by its expansion, against the end of G, to complete the stroke and carry the crank M past its'dead-point, so that both the pistons K and cylinder G will be moving in the some direction as the air expands.

The crank 11, turning the centre befiu'ethe crank M, causes the distance between, g and K to increase, transferring the air from the hat D to the cylinder A, where it is cooled, to produce a minus 1n'essnre, that causes a reaction on the parts moving the piston K in the other direction, the crank M having by this time turned its dead-centre, and the operations are repeated.

What I claim, and desire to secure by Letters Patcut, is-

The air-heating cylinder, or hat, D, the cylinder A, with water-jacket \V, in combination with the di placement-cylinder G, piston K, and connections to the fly-wheel shaft, substantially in the manner set forth.

In testimony whereof, I have hereunto set my name, in presence of two subscribing witnesses, this 1st day of February, A. D. 1869.

W. LEHMANN.

Witnesses PHILIP GEISSE, NIGOLL HALSEY. 

